1. Field of the Invention
The invention relates to tool holders and refers more specifically to floating tool holders of a type wherein structure is provided to move a tool held thereby transversely with respect to the axis of the tool holder and/or pivot the tool with respect to the axis of the tool holder so that the axis of the tool is not parallel with the axis of the tool holder to permit minor alignment of the tool with openings to be machined which are not perfectly aligned with the axis of the tool holder.
The invention further relates to tool holders wherein compression means are provided in conjunction with the tool holder for permitting axial contraction of the tool holder in the event of greater misalignment of the tool with an opening to be machined, or in the event no opening to be machined has been provided, to prevent damage to the tool, tool holder, and/or workpiece. The invention further refers to such a tool holder wherein a quick-change coupling is provided to facilitate rapid installation of a tool on the tool holder and removal of the tool therefrom.
2. Description of the Prior Art
In the past, tool holders have generally been relatively rigid. That is to say, tool holders have been designed to secure a tool thereto on, for example, the axis of the tool holder. With such structure, as the tool holder is directed toward a workpiece, the axis of the tool holder must be aligned with openings in the workpiece to be machined by means of a tap tool or the like, for example, since slight misalignment of the hole, either due to translation of the axis of the hole with respect to the axis of the tool, or an angular displacement of the axis of the hole with respect to the axis of the tool may result in broken taps, damaged tool holders and/or workpieces.
Devices have sometimes been provided for permitting a slight translation of the tool within the tool holder to align the tool with the axis of the opening. In some very few instances, structure permitting both translation and pivoting of the axis of the tool to align the tool in misaligned openings has been provided. Such structure as has been provided in the past has, however, not included both possible movements or has been particularly complicated and therefore expensive and not generally efficient.
Such prior structure has further required the tool holder to have a considerably axial length which is undesirable in many machining operations wherein space for the tool holder is limited. In addition, such structures of the past have not always provided axial compression so that if a hole is totally misaligned with the tool in the tool holder, or if the hole is missing, the tool holder will contract on engagement of the tool with the workpiece.
Also in the past, tool holder structures have not always been provided with simple, efficient and economical quick-release couplings for mounting tools thereon. Thus, tool changing has been more difficult than necessary and has been time consuming and therefore expensive.